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Solve the World's Energy Needs? Any Non-Fusion Possibilities?

  1. Apr 20, 2006 #1
    What could potentially allow the world to create cheap, low-polluting energy? I imagine fusion could fit the bill. Is there anything else other than fusion? Could super conduction have a major impact?
    Last edited: Apr 20, 2006
  2. jcsd
  3. Apr 20, 2006 #2
    Well, if oil prices keep rising, the established alternatives( biofuel, solar, wind, etc...) are going to become much more financially viable.
  4. Apr 20, 2006 #3
    I think solar is cool. Combustion has been around for a while, I believe a creative mind is needed to "seek out new...possibilities" (StarTrek TNG). If only there were a way to overcome the conservation of energy / mass. I believe effeciency will be the more short term answer. Imagine all transmission lines fitted with superconductors :)
  5. Apr 20, 2006 #4


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    haha yes, im sure we all would want a way to get around COE.

    The problem is if you combine "world", "cheap", and "low-polluting", you have problems. The best possibilities will probaby not be cheap and probably not suitable for every region in the world. There are a lot of "potentials" out there... but i don't know anything about their feasibility. As far as super conductors are concerned, one thing is that if you can figure out how to create room temperature superconductance, you'll reduce energy needs simply because you can (if it's economical) replace the current lines with them.
  6. Apr 21, 2006 #5


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    I guess that spreading a desease that kills off 99.9% of the human world population would do too, but this is probably not the answer you were after :surprised :devil:

    As Ian Malcolm says, in Jurassic Parc, "Life will always find a way" :biggrin:

    No, seriously, in the relatively short term, I think a combination of solar, wind, bio and nuclear (fission) will have to replace as quickly as possible most fossile consumption. This becomes advantageous with high oil prices - let's hope they stay high and climb even higher.
    On longer term, who knows ? Fusion is yet to be seen ; I don't think it will be a major player in most of the 21th century.

    Contrary to what's often claimed in the media, superconduction will do almost zilch to any energetic consideration. All electrical power systems (generators, distribution etc...) is already 90+ % efficient.
  7. Apr 21, 2006 #6


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    Damn so i've been conned by the media again!
  8. Apr 21, 2006 #7
    I don\'t think (or at least I hope not) anyone would support such a measure. But it does identify the real problem.

    Seriously, the only way to solve the energy problem is to stop wanting so much energy.

    It is the same way with the hunger problem. Produce food more efficently, and the population just grows again needing more.

    Regardless of the energy sources of the future (fusion, whatnot), if they are finite, we will use it up and demand more. The only authentic long term solution is if we can somehow control our population.
    Last edited: Apr 21, 2006
  9. Apr 21, 2006 #8


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    Indeed, that's the entire problem: food, energy, ecology. The biggest problem on earth are kids. We should stop making them in such quantities.

    And there's another issue: imagine we arrive at develloping portable 500 GW fusion engines that are as big as an MP3 reader, with room temperature superconducting outlets, running on seawater. Have we solved the problem now ?

    Even if we do not go through a thermal cycle and have "direct electricity production" in the 500 GW production cell (haven't gotten the vaguest clue how to do this, we're in complete science fiction here), the 500 GW outlet will, in the end, turn into heat, no matter how you use it.

    Once this waste heat, produced by all the devices plugged onto these pocket fusion engines, starts competing with the energy flux the earth receives from the sun, we're in for a BIG climate change ! Even though the source is entirely "clean".
  10. Apr 21, 2006 #9


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    I would think that when we have a 500GW outlet, we'll have figured out a way to extract heat out of the atmosphere and get it off the planet....

    I wonder how much money is being put into technology for possibly extracting heat/greenhouse gases from the atmosphere. I also wonder if the only barriers to such technology is money.... since money is just a man-made idea that theoretically can be halted or manipulated in such a way as to make it work out. I mean when you're dealing with such a problem, money should not stand in the way.
  11. Apr 21, 2006 #10


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    It's difficult, you know. After all, unless changing entirely earth's surface, or the atmosphere's composition, the number of infrared photons emitted is determined by the composition of the atmosphere and the surface temperature.

    For instance, you cannot put some giant airco somewhere. You'd produce waste heat that overcompensates what you try to gain. However, you could cover the earth with some kind of aluminium foil :-)

    Oh, and BTW, never ever shortcircuit that 500 GW outlet :rofl:
  12. Apr 21, 2006 #11
    Get enviromtilest gourps and go to the suprme court and delcare the laws of physiscs are unconstional.

    What about nuclear fisson?If we could find a way to make them safer and more effencent wouldn't that help solve the world's energy needs?
  13. Apr 21, 2006 #12
    Well nuclear energy would be more feasible if we had superconductors. We could build the power plants in remote locations and then export electricity to the cities.

    I'm sure oil prices will go up, but that might not have a huge impact on wind/solar/nuclear/biofuel. The latter group is less practical than coal, and coal is cheaper than oil.
  14. Apr 21, 2006 #13


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    I'm not sure I understand your fascination with "superconductors", and how it can do anything to "solve the world's energy needs".

    1. We DO already have nuclear power.

    2. We DO already have superconductors.

    So? The amount of energy 'waste' isn't significant if all you care about is electricity transport. This isn't going to solve anything.

  15. Apr 21, 2006 #14


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    An interesting article in Science (Vol 310, 18 Nov. '05, page 1106) highlighted the future of oil production in the world. They predicted "a brief sigh of relief" in the next 5 to 8 years as various sources come on line. However, after that, they predict demand will outstrip supply. On the second page of the article, there's a review of alternatives which highlights various possibilities and their expected contribution in replacing oil..

    The problem I see is if we could convert heavy oil, oil sands, coal and natural gas to liquid fuel, the global warming problem could present us with even more difficult challenges. I don't like the term "global warming" because it really doesn't due justice to the issue. An interesting article in Scientific American a month or so ago discussed ocean acidification due to the sudden rise in atmospheric CO2, and that's just part of the issue. Local changes in weather patterns threaten to change the landscape considerably, and ocean level rises threaten to change things further. The right answer isn't more fuel that creates CO2, the right answer is renewable resources IMHO and possibly fission or fusion energy. Note the article above doesn't acknowledge the possibility of electrically powered vehicles and I'm not sure why. I have to respect the journal but they certainly can have rather pesimistic views of the future.

    Regarding how our energy consumption/expenditure may affect global warming, I'd have to respectfully disagree with vanesch:
    I think you can convince yourself that 'free energy' such as that suggested will have a negligable affect on global warming if you consider the enormous amount of solar energy incident on the earth. In comparison to our needs, I believe the amount of incident solar energy is a few orders of magnitude larger.
  16. Apr 21, 2006 #15


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    Actually I believe there was a post on this forum a short while ago about a professor who actually did the calculations and said that within a few decades (i think), the rate of manmade heat will be 7x the heat incident on the earth from the sun. I believe the thread was about someone on our forum that miscalculated how long fusion could work for the world and eventually someone brought that study showing how this heat problem would come up if or when we were able tos olve our energy supply problems.
  17. Apr 21, 2006 #16


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    Price of crude oil (1947-2004) - http://www.wtrg.com/oil_graphs/oilprice1947.gif

    Price of oil and gas - http://www.wtrg.com/prices.htm


    Checking NYMEX - June 2006 $75.12 light sweet crude, and futures for through Nov 2006 are between this price and up to about $77/ barrel.

    Gasoline prices will like exceed $3.00/gal in much of the US this summer.


    Natural gas is running about $8 mmBTU, and since most gas fired plants were built with anticipated prices of between $2-3 mmBTU, many gas fired plants are offline.


    The problem is two-fold. Demand for energy is high, and often for wasteful purposes. The production of energy is relatively inefficient.

    Solution - reduce wasteful use of energy, and improve efficiency of production.
  18. Apr 22, 2006 #17


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    I hope you understood that I said that half-jokingly !
    The point was that even if the source is entirely clean, that there is yet another limit to power production, which is when its total production starts to be comparable (say, 1%) of the total incident solar flux. That's a huge flux, I know, but it is a finite limit in any case.
    Power flux from the sun, say: 1KW / m^2.
    Total "cross section" of the earth: 1.3 10^14 m^2, so total solar power flux: 1.3 10^17 W. 1% of this: 1.3 10^15 W
    Number of 500 GW MP3 units corresponding to this: 2500.

    http://en.wikipedia.org/wiki/Orders_of_magnitude_(power [Broken])

    Power consumption in the world in 2001: 1.3 10^13 W
    So we're indeed still two orders of magnitude removed from this. In other words, 25 of these 500 GW MP3 units would do, for the moment...

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  19. Apr 22, 2006 #18
    hi, first post here-

    question regarding this issue- if one would have a 40 miles long electric cable, would it be possible to strech it from earth's mainland to outerspace? i mean physically, is it possible to do that?

    i ask that because solar energy inside earth is really lousy because of maintance and land costs and also the damaging effect of silicon-but if you would build a huge powerplant based on solar energy in orbit of earth, which is probably possible, all you would need is a cable that hold until the bottom of the earth...?
  20. Apr 22, 2006 #19
    You dont need a cable at all. You can beam down the energy with microwaves. Building and launching solar panels into space in enough quantities to make a impact on energy production would cost ALOT.
  21. Apr 22, 2006 #20
    hmm so maybe there is silicon near us? we could build the glass in the american space station..or maybe just getting the raw materials and build the plates in orbit..

    microwave is 100% efficiancy when beaming from space to earth?
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